pgsql: Fix Windows-only postmaster code to reject a connection request

Log Message:
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Fix Windows-only postmaster code to reject a connection request and continue,
rather than elog(FATAL), when there is no more room in ShmemBackendArray.
This is a security issue since too many connection requests arriving close
together could cause the postmaster to shut down, resulting in denial of
service.  Reported by Yoshiyuki Asaba, fixed by Magnus Hagander.

Tags:
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REL8_1_STABLE

Modified Files:
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    pgsql/src/backend/postmaster:
        postmaster.c (r1.475.2.1 -> r1.475.2.2)

(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/postmaster/postmaster.c.diff?r1=1.475.2.1&r2=1.475.2.2)